Not every uniform is an employee uniform
For context, I’m from Brazil and most schools here have an official uniform you must wear. My school’s t-shirt was white and had the name of the school stamped on the front and back of the shirt.
I was around fifteen, shopping at a grocery store (where the employees’ uniform is orange) with my mom across from my school. I was checking something out alone in one aisle when one woman approaches me and immediately asks something about a product. I told her that I didn’t know, a bit awkward because I was an extremely introvertes teen and there was a strange lady talking to me. The lady huffs and asks if I don’t work there. I answer that no, I don’t. And with all this information this crazy woman looked at me and said “well, you are wearing an uniform, I thought you worked here”. I guess I just told her no again and she stared at me extremely pissed before walking off. Very strange interaction with someone who seems to assume that if you wear an uniform, any kind, you work there.